Have you ever encountered in the wild (i.e. owned, considered purchasing in a store, seen worn by an observant Jewish man) a garment that requires tzitzit but that was not made for them (i.e. not a tallit gadol or tallit katan)?

If you've seen such a garment worn by an observant Jewish man, how was it handled? Were tzitzit added? Was the garment altered to remove the requirement?

I'm asking because it seems to me that this situation is rare in the modern Western world and therefore the relevant rules may be forgotten when it does come up, so it could be useful to have a collection of practical anecdotes, to spread awareness of both how the issue manifests in real life and how it can be dealt with. Also, I'm just curious about what people have seen.

Rav Yoel Bin Nun famously slit the slides of his suit jacket rov open and attached tzitzit (with techelet) because he wants to be yotzei the mitzvah on his regular beged as is likely the intention of the pasuk. Source: I've seen him!

When members of the Neturei Karta movement in Meah Shearim protest the State of Israel on Yom Ha'atzmaut, they dress in sackcloth, which has four corners (at least that's the current style). I noticed that at least one corner of every sackcloth garment was rounded off, but it could be because of the poor-quality sackcloth, which is in high demand around Yom Ha'atzmaut.

Back in the "Ugly 80's" there was this muscle shirt that had the sides slit all the way up until almost the armpits, creating a four cornered shirt. No one I saw wearing it knew or cared about Hilchos Tzitzis.

I was once part of a traveling Chanukah play (long story) in which I acted1 as an evil (didn't have to fake it too much >;-) ) king (you'll never guess which!)2. On one piece of the king's (very elaborate) costume (I think it was the cape) we had a safek on whether it needed tzitzis. Of course, we only realized this in between scenes. On the sixth performance. For a special-needs school. In Yehupitzville.

So one of the guys grabbed a scissors and rounded all of the corners. Just to be safe. We then finished the play and went on to perform it eight more times. In three days. In four cities. Good times!

(Sorry for stretching it out, I'm gearing up for Purim. =D)

1) I also sang and played the guitar. It's an interesting story. Remind me to tell you sometime.2) Okay, fine, it was Achashverosh.

Just a few days ago I saw a frock coat with a generous slit down the back and tried to eyeball it to see whether it came out to rov pasuach. Close call. Then I stole glances at the wearer, both front and back, in search of rounded corners and didn't see any. So I was dan lekav zechus and assumed the slit went less than halfway up.

If I understood correctly, according to Pe'er Halacha you count the lapels as corners, so there are actually six, which means you'd have to round off at least three.

There are these rain coats that are sort of a large 4 cornered heavy material with snaps at the bottom. I saw someone who wore it and after someone pointed out to him that it may be a Shaila of Tzitzis he rounded off the corners.

Unless the synthetic material was cut down to threads an rewoven, there would not be a shaila. It would be similar to leather which the Mishna Berura 10:11 brings as not requiring even d'rabanan: hebrewbooks.org/…
–
YDKJan 16 '11 at 19:28

@YDK What about a nylon rain poncho with Ripstock? I a had a poncho like this once, and didn't know if it was considered woven or not, so I rounded off one of the corners.
–
MenachemMay 30 '11 at 9:12